Identification of Subsurface Water Pipe Based on Horizontal to Vertical Spectral Ratio (HVSR)

Disruption of water distribution through underground pipe is a frequent case. As a handling, a method that can detect disturbances from subsurface pipe is needed. Microtremor is one of the geophysical methods that can provide an overview of the subsurface. Processing is done with the HVSR method with input in the form of seismic waves in the time domain which is then processed using Geopsy software to get output in the form of dominant frequency values, amplification, and H/V spectrum. The data used in this study are primary data obtained from data acquisition with a total of 60 measurement points. The distance between points is given 5 dm with a measurement time of 10 minutes for each point. The study was conducted on pipe with empty, partially filled with water, and fully filled with water with a pipe diameter of 0,9 dm. The pattern in each pipe condition from the modeling results appears at a frequency of 0-10 Hz. The difference in the range of amplification values in pipe anomalies is due to different levels of water content which can be concluded that pipe filled with water have higher amplification than empty pipe and be showed in 3D modelling.